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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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54                                 ALASKAN GLACIER STUDIES
of Malaspina Glacier were covered with ablation moraine. This was recorded by notes and in a sketch map and photographs (PL XHI, A). Dirty, somewhat crevassed ice was observed along the border of the Hitchcock Hills toward the point of emergence of Seward Glacier, in Malaspina Glacier down to what was then taken to be Kame Stream, and thence eastward parallel to the glacier margin. Outside this moraine belt was clear ice with the morainic scrolls previously alluded to. There was no lake visible near Blossom Island. The Marvine Glacier, however, was apparently not crevassed, in its valley, and seems to have been almost exactly as when traversed by Russell in 1890. The whole eastern Malaspina Glacier, although not seen from nearer than this, seems to have been in the fall of 1905 essentially as it had been when crossed by the expeditions of 1890,1891, and 1897, except in the portion near the east border where crevassing had then commenced. Near the debouchure of Marvine and Hayden Glaciers the moraine-veneered ice was broken into flat-topped tables or seracs, but practically none of the de*bris had as yet disappeared into the crevasses. Its condition was not unlike that of lower Lucia Glacier in 1909. In view of the remarkable extension and continuation of crevassing observed by the senior author in 1906, this beginning of crevassing in 1905 is of much interest,1 especially as this wave of advance which produced the crevassing seems to have appeared in the piedmont bulb before it affected the valley glacier. This area of crevassing is similar to the much smaller one seen in Atrevida Glacier the same year. Our impression was that even the crevassed area could have been crossed in August, 1905; but in 1906 this part of the Malaspina Glacier was impassable.
Advance of Marvine in 1906. The expedition of 1906 had for its object the crossing of Malaspina Glacier from east to west and the further study of this piedmont ice mass; but by a sudden and most unexpected change in the condition of the eastern or Marvine lobe this plan was thwarted. The nature of this change, as observed along the eastern margin of the Malaspina Glacier from Point Manby to Blossom Island, has been fully described2 elsewhere, and will only be summarized here.
Where Marvine Glacier emerges from its mountain valley above Blossom Island the progress of the expedition of 1906 was absolutely barred by a sea of crevasses and bristling pinnacles (PL XIV), the entire glacier surface from side to side, for a width of fully 4 miles, being broken as only rapidly-moving glaciers are, and resembling an ice fall in the intensity of the breaking. Yet it was at this very point that Russell had easily crossed in 1890, carrying his entire outfit toward Mount St. Elias. From this point down to the sea the surface of the Marvine lobe was broken into an impassable condition, and the margin of the glacier was also continuously broken except where joined by the Hayden Glacier, by which the area of crevassing was pushed out from the mountains. We could not get far out upon the glacier at any point along the margin, for everywhere the way was barred by an impassable network of crevasses. This condition of breakage extended even to the shores of Yakutat Bay, and across the routes followed by Russell on his retreat in 1891 and by the Bryant and Abruzzi expeditions in 1897. The area
* The fact of this beginning of crevassing in 1905 was not seen by the senior author, who did not cross Atrevida, Lucia, or Hayden Glacier in 1905.   It was not known to him when be wrote the several papers on the 1906 conditions in which he has assumed that the crevassing began between August, 1905 and June, 1906.   We did not see the area together in either 1905 or 1906 and the recorded observation of crevassing in 1905 has only been noticed since our 1909 expedition.
 Tarr, R. S,, The Yakutat Bay Region, Alaska, Professional Paper 64, U. S. Geol. Survey, pp. 83-88; Tarr, H. S., Bull. Geol. Soc. America, Vol. 18,1907, pp. 273-277.